Engine and drive train suspension system for snowmobiles

Abstract

An improved snowmobile construction in which the entire power train from engine to track drive member is rigidly mounted in bearings in a cradle member, and the latter is resiliently mounted on the housing of the snowmobile. In one embodiment the snowmobile skis are also mounted on the cradle member. In a second embodiment the skis are mounted on the housing, and the forward portion of the cradle is additionally interconnected resiliently with the housing.

We claim as our invention: 
     
       1. In a snowmobile including a rearward track and forward ski members: a housing enclosing said track;   a track drive member passing through said housing;   a source of mechanical energy of rotation coupled to said drive member external to said housing;   and cradle means including a pair of spaced rigid plate members resiliently mounting said source and said drive member on said housing.   
     
     
       2. The structure of claim 1 in which said ski members are secured to said housing. 
     
     
       3. The structure of claim 1 in which said ski members are secured to said cradle member. 
     
     
       4. The structure of claim 1 in which said source is rigidly mounted in bearings on said cradle. 
     
     
       5. In a snowmobile including a rearward track and forward ski members; a housing enclosing said track;   a track drive member passing through said housing;   a source of mechanical energy of rotation coupled to said drive member external to said housing;   and cradle means resiliently mounting said source and said drive member on said housing, said cradle means including discs of resilient material coaxial with the drive member, and means securing the opposite faces of each disc to said housing and cradle respectively.   
     
     
       6. The structure of claim 5 including means remote from said discs for further resiliently interconnecting said housing and said cradle. 
     
     
       7. The structure of claim 5 in which said discs comprise the only mechanical connection between said cradle member and said housing. 
     
     
       8. In a snowmobile including a rearward track enclosed in a housing and forward ski members, in combination: an engine having a throttle to vary the speed thereof;   a jack shaft;   centrifugal clutch means transmitting power from said engine to said jack shaft;   a track drive member passing through the housing;   a chain drive enclosed in a chain case and transmitting power from said jack shaft to said track drive member;   a cradle member;   means rigidly supporting said engine, said jack shaft, and said drive member in bearings in said cradle member;   and means resiliently supporting said cradle member on said housing, including a pair of discs of resilient material having first faces secured to said housing and second faces secured to said cradle member.   
     
     
       9. The structure of claim 8 in which said discs are located coaxially with said drive member. 
     
     
       10. The structure of claim 8 in which said discs comprise the only mechanical connection between said cradle member and said housing. 
     
     
       11. The structure of claim 8 in which said ski members are connected to said cradle member. 
     
     
       12. The structure of claim 8 including means remote from said discs for further resiliently interconnecting said housing said cradle member. 
     
     
       13. In a snowmobile including a rearward track and forward ski members: a housing enclosing said track;   a track drive member passing through said housing;   a source of mechanical energy of rotation coupled to said drive member external to said housing:   and cradle means resiliently mounting said source and and said drive member on said housing, said cradle means including first and second spaced rigid plate members and a rigid engine mount interconnecting said plate members.   
     
     
       14. The structure of claim 13 in which said ski members are secured to said plate members at forward portions thereof. 
     
     
       15. The structure of claim 13 in which said plate members are resiliently interconnected with said housing at forward portions thereof.